St. Marien Fachklinik für Rehabilitation GmbH & Co. KG in Bad Soden-Salmünster relies on a climate-friendly and efficient energy supply. A key component of this is a modern heating centre with a combined heat and power unit - built and operated by Stadtwerke Gießen.
Bad Soden-Salmünster. Outdated heating systems with low efficiency are considered energy guzzlers and can drive up heating costs considerably. For this reason, St. Marien Fachklinik für Rehabilitation GmbH & Co. KG was also looking for a modern alternative to its outdated system. Together with Stadtwerke Gießen (SWG), the facility found the right solution - a combination of condensing boiler technology and combined heat and power (CHP). The new heating centre went into operation in April. Peter Diel, Head of Administration at St. Marien Fachklinik, is confident: "Thanks to the new system, we will significantly reduce our primary energy consumption, thereby substantially cutting both costs and emissions. We are delighted that Stadtwerke Gießen is supporting us with its many years of experience." Contact with the Central Hessian energy company was established via Curatis GmbH, based in Eschborn. The company advises and supports hospitals and care facilities in all aspects of facility management. Managing Director Ottmar Graf explains: "When we were looking for a suitable partner, we heard about the good experience that the Berglandklinik in Bad Endbach had had with SWG. The energy experts successfully implemented a project of a similar size there a few years ago."
Individual solution via contracting
In the case of the St. Marien Klinik, this is an energy contracting project with a leasing model. This means that SWG took over the entire conversion of the heat supply - from the generation to the distribution of heating energy and hot water. As the operator, SWG in turn leases the plant from the facility and supplies it with around 1.9 million kilowatts of heat each year.
The centrepiece of the new plant is a combined heat and power unit (CHP) with a thermal output of 212 kilowatts (kW) and an electrical output of 120 kW. "From now on, the clinic can cover part of its electricity requirements with the CHP unit. This eliminates both the grid fees and the electricity tax," explains Thomas Wagner, Head of Sales Industrial and Business Customers at SWG. In addition to the combined heat and power plant, Stadtwerke Gießen has also installed a condensing boiler in the heating centre. It contributes a thermal output of 500 kW.
Optimised heat distribution
SWG spent a considerable amount of the entire construction and renovation time modernising the heat distribution and heat output in the individual parts of the building and in the specialist clinic's swimming pool. "Many modernisations focus solely on replacing the generation systems. They forget that a lot of energy is lost on the way from the system to the radiators or until the hot water is used. And this is not only due to poorly insulated pipes. The holistic approach - as we pursue it - also takes this important aspect into account. This includes hydraulic balancing, which we have also carried out," explains Willi Schwarz, the responsible project manager at SWG.
The new system can be controlled and monitored remotely. Stadtwerke Gießen installed complex measurement, control and regulation technology for this purpose. In addition, the domestic hot water preparation system was completely rebuilt. Plate heat exchangers are now used to heat water and heat the swimming pool. "We have completed extensive refurbishment work that has raised us to a new level in terms of energy supply. We are now ideally positioned for the future," emphasises Peter Diel.